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The concave-eared torrent frog (Odorrana tormota) is the first species of tailless amphibian that was evidenced to phonate and detect ultrasounds.We employed anatomic and histological methods to examine the phonatory organs,including the floor of the buccal cavity,vocal cords and glottis,of O.tormota and its sympatric species including O.graminea,O.schmackeri,and Amolops wuyiensis with different fundamental frequencies,and Pelophylax nigromaculatus as a control.Our results reveal that O.tormota possesses specialized phonatory organ structures,with thinner vocal cords modulated by a moderately stronger muscular mastoideus between the medial vocal cords and the lateral cricoid cartilages,and more elastic mouth floor to likely supply faster air stream which could make the vocal cords vibrate at higher frequencies,larger relative distance between the two muscles m.intermandibulares (RDMI),and higher nucleus density of m.intermandibularis (NDMI) and m.geniohyoideus (NDMG).The results of Pearson's correlation tests between the mean values of the above measurements and the fundamental frequencies from the five species imply that all the specialized phonatory organ structures mentioned above might be favored by higher frequency ofphonation of O.tormota.